首先以Hummers法制备还原态氧化石墨烯(RGO),其次通过溶胶-凝胶法和水热法分别制备TiO_(2)和TiO_(2)/RGO复合材料,然后向硝酸银溶液滴加氨水沉淀出纳米Ag并掺杂到TiO_(2)上,再以聚乙烯吡咯烷酮(PVP)为分散剂,以RGO为基体材料,用一步水...首先以Hummers法制备还原态氧化石墨烯(RGO),其次通过溶胶-凝胶法和水热法分别制备TiO_(2)和TiO_(2)/RGO复合材料,然后向硝酸银溶液滴加氨水沉淀出纳米Ag并掺杂到TiO_(2)上,再以聚乙烯吡咯烷酮(PVP)为分散剂,以RGO为基体材料,用一步水热法合成Ag@TiO_(2)/RGO复合光催化剂。复合材料通过FT-IR、XRD、SEM、DRS和BET等进行结构、组成、形貌和孔径大小的表征。将Ag@TiO_(2)/RGO用来光催化降解罗丹明B(RhB)溶液,结果表明,0.020 g该催化剂对50 mL 5 mg/L的RhB溶液在pH值为5、室温条件下的降解效果最好;经6次循环利用后,降解率依然能达到80%。展开更多
1T-MoS_(2)nanosheets,with metallic conductivity and high capacity,hold great potential for lithium-ion capacitors(LICs),but suffer from sluggish reaction kinetics due to dense stacking.Herein,1T-MoS_(2)nanosheets with...1T-MoS_(2)nanosheets,with metallic conductivity and high capacity,hold great potential for lithium-ion capacitors(LICs),but suffer from sluggish reaction kinetics due to dense stacking.Herein,1T-MoS_(2)nanosheets with enlarged interlayer spacing,vertically bonded to reduced graphene oxide(rGO)(1T-MoS_(2)/rGO),were designed using a hydrothermal-assisted dispersion and intercalation strategy.The active nitrogen species derived from N,N-dimethylformamide(DMF)not only bridge the rGO and MoS_(2)through strong Mo-N-C bonds to promote the formation of dispersed MoS_(2)nanosheets,but also intercalate into the MoS_(2)structure,further enlarging the interlayer spacing.This unique structure synergistically enhances meso-and microscale mass transfer outside and inside of the few-layered nanosheets,significantly improving electrochemical reaction kinetics and reducing the kinetic mismatch between the anode and cathode.Consequently,the resulting 1T-MoS_(2)/rGO achieves a capacity of 500 mAh g^(-1)after 500 cycles at 5 A g^(-1)and a high rate performance of 587 mAh g^(-1)at a high rate of 10 A g^(-1).Moreover,the assembled 3D vertical 1T-MoS_(2)/rGO//AC LIC delivers a high energy density of 100.3 Wh kg^(-1)at a power density of1.0 kW kg^(-1),and long cycle stability with capacity retention as high as 91.02%after 5000 cycles at 2 A g^(-1).This work provides a generalizable strategy for engineering two-dimensional material-based electrodes,offering new insights into high-performance energy storage systems.展开更多
Ordered NiCo_(2)O_(4)/rGO nanowire arrays(NWAs)grown on a Ni foam substrate were synthesized using a template-free hydrothermal method and employed as an electrode with outstanding electrochemical properties for super...Ordered NiCo_(2)O_(4)/rGO nanowire arrays(NWAs)grown on a Ni foam substrate were synthesized using a template-free hydrothermal method and employed as an electrode with outstanding electrochemical properties for supercapacitors.After conducting a series of time-variable controlled experiments,the structure,morphology,and electrochemical properties of NiCo_(2)O_(4)/rGO NWAs were analyzed to find the most suitable growth time.Benefited from such unique array architectures,the designed NiCo_(2)O_(4)/rGO NWAs electrode demonstrates significant electrochemical properties,showing a specific capacitance of 2418 F·g^(-1)at a charge-discharge current density of 1 A·g^(-1).Moreover,it demonstrates exceptional stability,maintaining a capacity retention of 81.5%after undergoing 2,000 cycles,even when subjected to a current density of 10 A·g^(-1).The reason of high stability is that the spacing between the nanowire arrays is large and the diffusion resistance of the electrolyte is significantly reduced,which facilitates the diffusion of the electrolyte into the interior of the electrodes and establishes an effective contact with the surface of the nanowires.Furthermore,the NiCo_(2)O_(4)/rGO nanowire array grows directly on the Ni foam without binder,which establishes rapid electron transport pathways on the Ni foam substrate,resulting in excellent electrochemical properties.展开更多
为改善SnO_2-Fe_2O_3的电化学性能,通过一步水热法合成SnO_2-Fe_2O_3/rGO纳米复合材料,采用XRD、SEM、电化学工作站和蓝电电池测试系统,研究rGO加入量对SnO_2-Fe_2O_3/rGO复合材料的结构和电化学性能的影响.结果表明:rGO的掺入能很好地...为改善SnO_2-Fe_2O_3的电化学性能,通过一步水热法合成SnO_2-Fe_2O_3/rGO纳米复合材料,采用XRD、SEM、电化学工作站和蓝电电池测试系统,研究rGO加入量对SnO_2-Fe_2O_3/rGO复合材料的结构和电化学性能的影响.结果表明:rGO的掺入能很好地提高SnO_2-Fe_2O_3循环稳定性和倍率性能;对于SnO_2-Fe_2O_3/rGO50复合材料,在160 m A/g的电流密度下,100次循环后,放电比容量仍然保持596.9 m Ah/g,库仑效率为98%;即使在1 A/g的电流密度下,依然有366.6 m Ah/g的平均放电比容量.展开更多
文摘首先以Hummers法制备还原态氧化石墨烯(RGO),其次通过溶胶-凝胶法和水热法分别制备TiO_(2)和TiO_(2)/RGO复合材料,然后向硝酸银溶液滴加氨水沉淀出纳米Ag并掺杂到TiO_(2)上,再以聚乙烯吡咯烷酮(PVP)为分散剂,以RGO为基体材料,用一步水热法合成Ag@TiO_(2)/RGO复合光催化剂。复合材料通过FT-IR、XRD、SEM、DRS和BET等进行结构、组成、形貌和孔径大小的表征。将Ag@TiO_(2)/RGO用来光催化降解罗丹明B(RhB)溶液,结果表明,0.020 g该催化剂对50 mL 5 mg/L的RhB溶液在pH值为5、室温条件下的降解效果最好;经6次循环利用后,降解率依然能达到80%。
基金the financial support from the National Natural Science Foundation of China(No.52225208 and 51802131)the Training Program for academic and technical leaders in major disciplines of Jiangxi Province-Young Talents(No.20212BCJ23021)the Natural Science Foundation of Jiangxi Province,China(No.20232BAB204020).
文摘1T-MoS_(2)nanosheets,with metallic conductivity and high capacity,hold great potential for lithium-ion capacitors(LICs),but suffer from sluggish reaction kinetics due to dense stacking.Herein,1T-MoS_(2)nanosheets with enlarged interlayer spacing,vertically bonded to reduced graphene oxide(rGO)(1T-MoS_(2)/rGO),were designed using a hydrothermal-assisted dispersion and intercalation strategy.The active nitrogen species derived from N,N-dimethylformamide(DMF)not only bridge the rGO and MoS_(2)through strong Mo-N-C bonds to promote the formation of dispersed MoS_(2)nanosheets,but also intercalate into the MoS_(2)structure,further enlarging the interlayer spacing.This unique structure synergistically enhances meso-and microscale mass transfer outside and inside of the few-layered nanosheets,significantly improving electrochemical reaction kinetics and reducing the kinetic mismatch between the anode and cathode.Consequently,the resulting 1T-MoS_(2)/rGO achieves a capacity of 500 mAh g^(-1)after 500 cycles at 5 A g^(-1)and a high rate performance of 587 mAh g^(-1)at a high rate of 10 A g^(-1).Moreover,the assembled 3D vertical 1T-MoS_(2)/rGO//AC LIC delivers a high energy density of 100.3 Wh kg^(-1)at a power density of1.0 kW kg^(-1),and long cycle stability with capacity retention as high as 91.02%after 5000 cycles at 2 A g^(-1).This work provides a generalizable strategy for engineering two-dimensional material-based electrodes,offering new insights into high-performance energy storage systems.
文摘Ordered NiCo_(2)O_(4)/rGO nanowire arrays(NWAs)grown on a Ni foam substrate were synthesized using a template-free hydrothermal method and employed as an electrode with outstanding electrochemical properties for supercapacitors.After conducting a series of time-variable controlled experiments,the structure,morphology,and electrochemical properties of NiCo_(2)O_(4)/rGO NWAs were analyzed to find the most suitable growth time.Benefited from such unique array architectures,the designed NiCo_(2)O_(4)/rGO NWAs electrode demonstrates significant electrochemical properties,showing a specific capacitance of 2418 F·g^(-1)at a charge-discharge current density of 1 A·g^(-1).Moreover,it demonstrates exceptional stability,maintaining a capacity retention of 81.5%after undergoing 2,000 cycles,even when subjected to a current density of 10 A·g^(-1).The reason of high stability is that the spacing between the nanowire arrays is large and the diffusion resistance of the electrolyte is significantly reduced,which facilitates the diffusion of the electrolyte into the interior of the electrodes and establishes an effective contact with the surface of the nanowires.Furthermore,the NiCo_(2)O_(4)/rGO nanowire array grows directly on the Ni foam without binder,which establishes rapid electron transport pathways on the Ni foam substrate,resulting in excellent electrochemical properties.
文摘为改善SnO_2-Fe_2O_3的电化学性能,通过一步水热法合成SnO_2-Fe_2O_3/rGO纳米复合材料,采用XRD、SEM、电化学工作站和蓝电电池测试系统,研究rGO加入量对SnO_2-Fe_2O_3/rGO复合材料的结构和电化学性能的影响.结果表明:rGO的掺入能很好地提高SnO_2-Fe_2O_3循环稳定性和倍率性能;对于SnO_2-Fe_2O_3/rGO50复合材料,在160 m A/g的电流密度下,100次循环后,放电比容量仍然保持596.9 m Ah/g,库仑效率为98%;即使在1 A/g的电流密度下,依然有366.6 m Ah/g的平均放电比容量.
